Esala Full Moon Poya is one of Buddhism’s most historic days. It commemorates the conception and renunciation of Prince Siddhartha, the Buddha’s first sermon at Isipatana (introducing the Four Noble Truths), and the founding of the Sangha. In Sri Lanka, Esala is marked by temple observances and the world-famous Kandy Esala Perahera, honoring the Sacred Tooth Relic of the Buddha.